Machine for centrifugally casting pipes



P. E. LORANG MACHINE FOR CENTRIFUGALLY CASTING PIPES April 15, 1969 Sheet Filed OCT.. 10, 1956 \&

M N w m Aflarney April 15, 1969 P, E. L ORANG 3,438,427

MACHINE FOR CENTRIFUGALLY CASTING PIPES Filed oct. 1o, 196e sheet 2 of 4 April 15, 1969 P, E, LORANG 3,438,427

MACHINE FOR CENTRIFUGALLY CASTING PIPES Filed oct. 1o. 196e sheet 3 of 4 ill "i L rw U 1 Afvrney April 15, 1969 Filed OCT.. lO. 1966 P. E. L ORANG MACHINE FOR CENTRIFUGALLY CASTING PIPES Ma/ZUM Sheel Tri-9.8

United States Patent O 3,438,427 MACHINE FOR CENTIIUUGALLY CASTING P E Pierre Edouard Lorang, Nancy, France, assignor to Centre de Recherches de Pont--Mousson, Pont-- Mousson, France, a corporation of France Filed Oct. 10, 1966, Ser. No. 585,368 Claims priority, application France, June 21, 1966,

66,219 Inf. c1. Bzzd 15710, 13/02 U.S. Cl. 164 295 11 Claims ABSTRACT F THE DISCLOSURE 'The present invention relates to centrifugally casting tubular bodies and more particularly to machines of the t-ype in which the rotary mould or shell is mounted on a stand having a variable inclination.

Machines of this type are known which are employed for casting thick-walled short tubular bodies. These machines have no casting trough and are fed with liquid metal by a pouring ladle which pours the metal into the mould in a single jet. The metal, which partially ills the mould, is `distributed over the wall of the latter by centrifugal force and forms a cavity whose shape depends on the inclination of the stand, that is, the inclination of the mould driven in rotation. During the casting it is necessary to modify the inclination of the mould since in the course of filling the mould the inclination must be high so as to enable the mould, which forms a container, to retain the metal, and prevent it from overflowing. Thereafter, as centrifugal casting proceeds, the inclination must be reduced and iinally becomes nil so as to produce a tubular body having a cylindrical cavity. At the end of the centrifugal casting period the mould therefore resumes the horizontal position and facilitates the withdrawal of the cast tubular body.

If it were contemplated to maintain a certain inclination of the stand of such a machine `during the casting, only jacks would be provided for maintaining this inclination. Under these conditions the stand would not rest on a rigid support. In any case, the solution would not be suitable for a machine of large size and volume.

Moreover, in the case of a centrifugal casting machine of the de Lavaud type provided with a casting trough or spout, such as the machine disclosed in French Patent No. 520,902, it is also necessary to vary the inclination of the stand in accordance with the diameter of the tubular bodies to be cast, the smaller diameters being cast with a greater inclination than the large diameters. The inclination of the machine is modied therefore only when the diameter of the casting moulds or shells are changed. For this reason it is usual to construct as many machines having a iixed stand of different inclinations as there are diameters of pipes to produce. This is a costly solution.

The object of the invention is to provide a machine for centrifugally casting tubular bodies which has both the advantages of the system including a pivoted stand and those of the fixed stand system having rigid supports or 3,438,427 Patented Apr. 15, 1969 ICC bases. The machine according to the invention comprises a stand which is pivoted to a horizontal transverse pin and rests on the ground through pairs of superimposed blocks of which one block is fixed and the other movable, one of said blocks having a single bearing face whereas the other comprises a step-like bearing face, a control device for shifting the blocks with respect to each other in each pair so that in each pair of blocks the blocks are iu mutual contact by the required step of the step-like face.

By means of this arrangement, it is possible to adjust precisely the inclination of the stand of the machine while affording the latter a iirm and strong seating. Further, great economy is gained since a single machine can produce a wide range of products.

Further features and advantages of the invention will be apparent from the ensuing description with reference to the accompanying drawings.

In the drawings:

FIG. 1 is a diagrammatic elevational view of a machine according to the invention;

FIG. 2 is a cross-sectional view of the machine taken along line 2 2 of FIG. l but on an enlarged scale;

FIGS. 3 and 4 are partial sectional views on the same scale as FIG. 2 and taken along lines 3 3 and 4 4 of FIG. l respectively;

FIG. 5 is a longitudinal sectional view taken along line 5 5 of FIG. 4;

FIG. 6 is a sectional view of a detail of the machine according to the invention on a smaller scale than that of FIGS. 2-5;

FIG. 7 is a view similar to FIG. 1 of the machine in the course of changing the inclination of the machine;

FIG. 8 is a view similar to FIG. l in the case of a pipe having a larger diameter; and

FIG. 9 is a View similar to FIG. 5 of a variant of the invention.

In the embodiment shown in FIGS. 1-8 the invention is applied to a centrifugal casting machine for example of the de Lavaud type for casing pipes T (FIGS. 1 and 8).

This machine comprises a pivotal pouring ladle A which pours the molten metal into a trough or spout B. The latter pours the metal into the shell or mould C carried by a carriage D which is movable along a runway. Movable in the axial extension of the mould-support carriage D and its runway, is a withdrawing carriage E which is adapted to take hold of the cast pipe and withdraw it from the mould. The withdrawing carriage E is also movable along a runway.

The stand is a composite braced girder 1 comprising for example H-section members (see FIG. 2). This girder 1 supports the runway for the carriage C, the ladle A and the trough B. Likewise, the runway of the withdrawing carriage E is carried by a braced composite girder 2 which is in the extension of the girder 1.

According to the invention, the girders 1 and 2 are pivotally interconnected at their adjacent ends by a common horizontal shaft or pin 3 (FIGS. l and 2) carried by bearings, the girder 1 being connected to the shaft 3 by a depending portion 4al and the shaft 2 being connected to the shaft 3 by an extension 2a.

At their other ends the girders 1 and 2 are raisable or lowerable by jacks 5 and 6 pivoted to supports 7 and 8.

The girders 1 and 2 can be supported at various points in their lengths and in accordance with variable inclinations, while remaining in the axial extension of each other, by pairs of blocks, for example three pairs of blocks.

Each pair of blocks comprises a lower block 9 carried by a iixed support 10 and provided with a single upper bearing face 11, and an associated upper block 12 whose active lower bearing face 13 is in the shape of inverted steps.

All the upper movable blocks 12 can 4lne moved simultaneously with respect to the fixed lower blocks 9 in the longitudinal direction of the machine. For this purpose, the girder 1 carries a longitudinally extending lead-screw 14 mounted, for example but not exclusively, on its longitudinal axis by means of a oating suspension. This floating suspension is for example a-rranged in the following -manner (FIG. 6). A number of brackets 15, for example secured to the bracing members of the composite girder 1, are provided with vertically elongated apertures 16. Slidable in each of the apertures is a pair of pins 17 rigid with a lug 18 which carries a sleeve 19 (FIGS. l and 6) in which a non-screwthreaded portion of the lead-screw 14 is journalled. This lead-screw is prevented from moving axially relative to the sleeve 19 by, for example, two pins 20 (FIG. 1) which extend through the lead-screw. At one end the lead-screw 14 can be rotated by a handwheel 21.

Cooperating with lead-screw 14 are therefore the upper blocks 12 having the stepped bearing faces. Each of the blocks 12 constitutes a movable carriage which is suspended by rollers 22 from the treads of the H-section members of the composite girder 1. For adjusting the blocks, the rollers 22 are rollable on the upper face of the flanges of said treads (FIG. 3). In the operative machine position, the blocks 12 act as a support for the girder 1 through their upper faces 23 which `are in contact with the lower treads of the H-section members of the girder (FIG. 4).

Each block 12 carries a sleeve 24 which forms a nut for the lead-screw 14 for the purpose of shifting the block.

The heights of the steps of the stepped face 13 can be equal or different. They are provided -for inclining the stand 1 at different inclinations on the order of only a few degrees from a minimum value of on the order of 1.

The fixed blocks 9 have such heights as to support the blocks 12 on the three blocks 9 simultaneously so as to ensure a good distribution of the load of the stand and machine.

The girder 2 carrying the runway of the withdrawing carriage E also has an inclination which is adjustable by means of blocks and other means `similar to those pertaining to the girder 1 and carrying the same reference numerals to lwhich the letter a has been added. The stepped blocks 12a and the corresponding fixed blocks and supports 9a and 10a are for example two in number instead of being three.

The machine according to the invention `operates in the following manner:

For small-diameter pipes having, for example, a diameter of about 50-60 mm., the stand of the machine must be inclined to the horizontal to the maximum extent. This inclination is necessary for the flow of the liquid iron in the casting trough. A rapid ow is necessary and results from the slope or inclination so that the stream of liquid iron of very small section has no time to cool and obstruct the trough. However, this inclination is small, and is on the order of merely a few degrees. As can be seen, the girders 1 and 2 are in exact alignment with each other. The girder 1 rests on the spaced Iblocks 9 through the stepped-blocks 12 (FIG. 4), the rollers 22 being then raised olf the lower treads or anges of the girder 1. The blocks 12, which support the girder 1 by their upper faces 23, rest against the fixed blocks 9 by one of the steps of their stepped lower bearing faces 13. However, the jacks are in their withdrawn position relative to the girder 1 so as to allow the girder to be supported solely by the stepped block 12. The same is true of the girder 2 which rests under the same conditions on the fixed blocks 9a through the adjustable blocks 12a. However, it should be mentioned that the girder 2 is on the other side of the pivot shaft 3 and it is 'by the upper steps of their stepped faces 13a that the movable blocks 12a rest on the xed blocks 9a.

The girders 1 and 2 behave in the manner of relatively elastically yieldable girders which bear on a plurality of supports (stepped blocks 12, 12a, xed blocks 9, 9a and supports 10, 10a). These various supports are necessary owing to the movement of mobile loads, namely the carriage D and the withdrawing carriage E.

If it is desired to change the production, that is, cast pipes having a large diameter, for example the largest diameter it is possible to cast von `the machine namely of around 300-400 mm. (FIG. 8), it is necessary to change the casting mould and reduce the inclination of the support. Indeed, the rate of ow of the iron in the pouring trough can be lower since the section of the stream of liquid iron is greater and the cooling of this stream rtakes longer. However, and above all, an excessively rapid ow must be avoided since otherwise it would result in a sudden contact of the iron with the 4mould and splashes inside the latter. The inclination therefor does not exceed a value of around 1. By means of the jacks 5, `the girder 1 is raised and pivots about the horizontal pivot shaft 3. The stepped blocks 12 are raised from the fixed blocks `9 as seen in IFIGS. 3-7. At this moment the adjustable blocks 12 no longer serve as a support by their upper face 23 for the lower flanges of the girder 1 but are suspended from said flanges by the rollers 22 (-FIG. 3). The girder 1 being thus raised, the lead-screw 1'4 is rotated in lthe suitable direction by means of the handwheel 21 so as to shift the blocks 12 and bring the upper steps of their stepped faces 13 in front of the xed blocks 9. As can be seen in comparing FIGS. 1 and 7, the blocks 12 must be shifted ltowards the left (as viewed in these figures). After this adjustment, the jacks 5 are once more lowered so as to allow the girder 1 to rest on the blocks 9 through the blocks 12.

As concerns the girder 2, the same procedure is adopted. However, it is the lower steps of the stepped faces 13a which are brought in front of the blocks 9B. It should be noted -that during the raising of the girder 2 for shifting the stepped blocks 12a, the girder 2 is no longer in the geometric extension of the girder 1 but makes an angle therewith.

Owing to the invention, it is possible to adjust the inclination in a precise manner while ensuring for the machine a strong and r-m seating on the steps of the stepped faces 13, 13a bearing on the blocks '9, 9a.

Further, a single machine capable of receiving moulds of different diameters ranging for example from a small diameter of around 50 mm. to a much larger diameter of around 30G-400 mm., is cap'able of casting pipes of different diameters my modifying the inclination of stand.

Consequently, the simple and strong structure according to the invention economizes several special machines for the different diameters of pipes to be produced and increases the range of possible production with a single machine.

FIG. 9 shows a variant of the invention in which the lead-screw 14, instead of being mounted as shown in FIG. 6, is journalled in supports such as .25 which are rigidly secured to lthe composite girder 1, whereas the stepped blocks 12 are mounted to float relative to the lead-screw 14. The blocks 12 are floatably mounted in the lpresently-described embodiment by means of n'ngs 26 which have vertically elongated apertures 27 and are rigid with the stepped blocks 12, these rings being mounted on each side of nuts 24' which are vertically movable and cooperate with the lead-screw 14 so as to shift the blocks 12 axially of the lead-screw.

Although specific embodiments of the invention have been described, many modifications and change's may be made therein without departing from the scope of the invention 4as defined in the appended claim's.

Thus the invention is also applicable to centrifugal casting machines which have no pouring trough. The invention is also applicable to machines provided with a pipe-withdrawing means which is fixed instead of being movable, this means being mounted on a fixed horizontal stand or on an extension of the girder 1 on the other side of the pivot shaft 3.

Further, instead of having a lead-screw 14 or 14a which cooperates with the stepped blocks lf2 or 12a, it is possible to provide a short lead-screw which cooperates with a nut rigid with a single stepped block, the device being completed by a linkage between this block and the others. In other Words, there could be only one driving stepped block which is shifted by a screw-and-nut mechanism, this block shifting the other blocks through rigid connecting links.

Instead of having two jacks 5 and two jacks 6 for raising the girders 1 and v2, a single jack 5 and a single jack 6 could be provided.

The stepped blocks could be fixed and rest on the ground, the cooperating associated blocks having a single bearing face being in this case movable along the composite girder or girders.

Having now described my invention what I claim as new and desire by Letters Patent is:

1. In a machine for centrifugally casting pipes, a structure comprising a stand pivoted to a transverse horizontal pivot shaft, pairs of superimposed blocks mounted on the ground and supporting the stand, one of the blocks of each pair of blocks being Xe'd relative to the ground and the other block being movable, one of the block of each pair of blocks having a single bearing face whereas the other block has a stepped bearing face, a control n device operatively connected to the movable blocks for moving the movable blocks relative to the fixed blocks, whereby in each pair of blocks the two blocks are in contact with each other by the desired step of said stepped face.i

2. A structure as claimed in claim 1, wherein the blocks having a stepped bearing face are movable and the blocks having a single bearing face are fixed.

3. A structure as claimed in claim 1, wherein the stepped bearing face blocks are Ifixed and the blocks having a single bearing face are movable.

4. A structure as claimed in claim 1, comprising at least one jack for supporting the stand at one of the ends of the stand and screw-andmut means for shifting the movable blocks.

5. A structure as claimed in claim 4, wherein one of the elements of the screw-and-nut means is oatably mounted.

6. A structure as claimed in claim 5, wherein each block carries a sleeve which is screw threaded and constitutes a nut for a lead-screw and a floatably mounted device suspends said lead-screw from the stand.

7. A structure as claimed in claim 6, wherein said floatably mounted device comprises brackets having vertically elongated apertures and vsaid sleeves are movably mounted in said apertures.

8. A structure as claimed in c'laim `6, comprising *fixed supports in which the lead-screw is rotatably mounted, the nuts being oatably mounted relative lto the movable blocks.

9. A structure `as claimed in claim 1, comprising rollers through which the movable blocks are suspended from the stand of the machine.

10. A structure as claimed in claim 1, wherein the movable blocks are arranged to support the stand of the machine by their upper faces.

11. A casting machine of the type having a casting trough and movable withdrawing means for withdrawing the cast tubular body, wherein the stand of said machine comprises two girders which are pivoted "to a common pivot shaft, each girder being combined with pairs of blocks, one of the blocks in each pair being fixed and the other movable, and one of the blocks having a single bearing face whereas the other block has a stepped bearing face; a control device for shifting in each pair of blocks one of the blocks relative to the other so that in each pair of blocks the two blocks are in mutual contact by the required step of said stepped face, and a jack for shifting said girders so as `to put the girders in axial alignment with each other at the required inclination.

References Cited UNITED STATES PATENTS 2,853,755 9/1958 Beyer 164-295 X I. SPENCER OVERHOLSER, Prmmj7 Examiner.

DEWALDEN W. JONES, Assistant Examiner.

U.S. Cl. X.R. 248-1; 164-298 

